Renal clear cell carcinoma with co-existing tumor thrombosis of renal vein and ureter: a case report and review of the literature.

When renal cell carcinoma locally spreads, it usually progresses along the renal vein and inferior vena cava. However, the spread along the ureteral lumen to the bladder is a rare situation. The author has only collected less than 30 similar cases. There is no standard treatment plan for patients with ureteral metastasis at present, and its pathological significance is also unclear. Here, we describe a 56-year-old male patient who presented to our hospital with fever and gross hematuria. After abdominal computed tomography (CT), we diagnosed him with a left renal malignant tumor and thickening of the left renal pelvis and ureter, considering metastasis. Later, cystoscopy was performed, and a ureteral tumor thrombus protruding into the bladder was found under the microscope. Then, laparoscopic radical nephrectomy of the left kidney and transurethral resection of bladder tumor were performed. After the operation, the patient's body temperature significantly decreased, and gross hematuria also improved. The pathology and related immunohistochemistry reported clear cell renal cell carcinoma. The patient has been discharged, and we plan to treat him with axitinib and toripalimab combination therapy as the subsequent treatment plan. This case demonstrates that surgical resection is still an effective treatment option for such cases, and we review the relevant literature and discuss the selection of surgical methods and pathological significance.